Locking and operating mechanism for a closure



May 23, 1961 w. H. BRAsKAM 2,985,447

LOCKING AND OPERATING MECHANISM FOR A CLOSURE Y Filed Feb. 7, 1958 2SHeets-Sheet 1 y 23, 1961 w. H. BRASKAMP 2,985,447

LOCKING AND OPERATING MECHANISM FOR A CLOSURE Filed Feb. 7, 1958 2Sheets-Sheet 2 United States Patent LOCKING AND OPERATING MECHANISM FORA CLOSURE Willem Hendrik 'Braskamp, Voorburg, Netherlands, assignor toN. Indnstriele Onderneming W. H. Braskamp, Rejswijk, Netherlands, acorporation of the Netherlands Filed Feb. 7, 1958, Ser. No. 713,926

Claims priority, application Netherlands Sept. 28, 1957 3 Claims. (Cl.268-74) The invention relates to a locking and operating mechanism for aflap, shutter, window, venetian blind or similar device operated bymeans of a flexible pulling member, the movement in one direction ofsaid device being obtained by means of a spring or by its own weightwhile the movement in the opposite direction takes place by means of thepulling member. Such mechanisms are used for flap windows, venetianblinds, ventilating flaps, shutters for window-ventilators and the likeand in their most simple and most occurring form are formed by a cord, acable or a chain, which has to be wrapped around a hook or has to besecured to a hook or nail by means of rings to fasten the device to beoperated in a certain position. The reliability of such a mechanism ofcourse depends on the handiness of the operating person or of thecondition of the hook or the like.

Purpose of the invention is the provision of a simple mechanism whichalways operates reliable and is easy to handle.

According to the invention this purpose is obtained due to the fact thatthe pulling member extends through a pipe mounted adjacent to the deviceto be operated and adapted to rotate about its own axis, that pipe beingbent downwards on the operating side and having a transverse groove inwhich engages a spring pressed strip, the width of which being greaterthan the length of the groove whereas that portion of the pulling memberextending through the pipe has been provided with thickenings adapted topass through the pipe but not underneath the strip extending into thegroove. The pulling member preferably is formed by a chain of sphericalor similar elements.

Due to that construction of the locking and operating mechanism hooks orthe like for securing the pulling member has become superfluous. Thelocking is obtained by means of the strip extending into the groove ofthe pipe said strip arresting the thickenings of the pulling member,which locking, however, may be raised easily by laterally pulling thepulling member such that the pipe is rotated as result of which thestrip is lifted by the edge of the groove.

This strip extending into the groove may be formed by a leaf springwhich is the most cheap and simple solution, whereas further the end ofthe strip or leaf spring cooperating with the pulling member may bebevelled somewhat for instance bent obliquely such that the thickeningsof the pulling member may be drawn underneath it in one directionwhereas a movement in opposite direction is prevented. This has theadvantage that on pulling the pulling member the pipe needs not to berotated to raise the locking since the strip or leaf spring may rideover the thickenings.

If the mechanism is used with a shutter which is maintained in the openposition by means of a spring, the

shutter may be brought in a more or less closed position 70 by pullingthe pulling member, in which position the shutter always will bearrested whereas lateral pullingv of the pulling member to raise thelocking is sufficient to again open the shutter by letting run out thepulling member in said lateral position.

The invention will be further elucidated with reference to the drawingin which the invention has been applied to a window-ventilator.

Figure 1 shows in cross-section a window ventilator with the lockingdevice according to the invention.

Figure 2 is a view on the back side of the lower portion of theventilator according to Figure l.

The window ventilator shown in the drawing consists of a motor 1 havinga fan 2 said motor being secured in a housing 4 by means of a bracket 3,that housing 4 being secured in the glass pane 6. This housing 4 isprovided with a cover 7 pivotally secured to the housing at 8, a spring9 being provided which urges the cover 7 in the open position. At thelower end of the cover at 10 a. pulling member 11 has been connectedextending through a pipe 12 mounted for rotation about its own axis inthe housing 4. Almost in the middle the pipe has been provided with agroove 13 extending unto the half of the thickness of the pipe, a leafspring 14 engaging that groove and having a width such that the springengages the edges of the pipe at the end of the groove. The pullingmember 11 is formed by a chain of spherical elements and the end of thespring 14 always extends between two balls of the chain. Due to this thechain is locked and consequently the cover 7. If in the open position ofthe cover 7 the chain 11 is pulled down that chain moves underneath theend of the spring thereby continuously raising the spring 14 until onestops pulling after which the chain is again locked by spring 14. If itis desired to open the cover 7 by means of the spring 9, the pullingmember 11 is pulled laterally as indicated in Figure 2 as a result ofwhich the end of the spring 14 is raised by the edge of the groove 13and moved out of engagement with the balls of the chain due to which thepulling member may move in opposite direction.

What I claim is:

l. A flap operating mechanism comprising a chain coupled to said flap,said chain including a plurality of connected links, a tubular guideslidably accommodating said chain whereby the chain is eifective toposition said flap, said guide being provided with an aperture exposingsaid chain, spring means extendible through said aperture for engagingthe chain and rendering the latter immobile, said spring means having asubstantially fixed position relative to said guide, and support meansrotatably supporting said guide to align and displace said apertureselectively relative to said spring means to render the latterrespectively elfective and inetfective to engage said chain, said guideincluding a radial extension through which said chain extends, saidchain bearing laterally against said extension to rotate said guide.

2. A mechanism as claimed in claim 1, wherein said spring means is aleaf spring having a free end adapted for engaging said chain.

3. A mechanism as claimed in claim 2, wherein the end of the springadapted for engagement with said chain is beveled.

References Cited in the file of this patent UNITED STATES PATENTS SwedenJan. 27, 1953

